The present invention relates to compositions and processes for making polyurethane foams. More particularly, it relates to compositions and processes incorporating tertiary amine catalysts capable of providing foams having reduced levels of odor and volatile emissions.
Polyurethane foams are widely known and used in automotive, housing and other industries. Such foams are produced by reaction of a polyisocyanate with a polyol in the presence of a catalyst and a blowing agent, historically a chlorofluorocarbon (CFC) compound. Due to environmental concerns relating to CFC's, the use of water blown foam formulations, in which at least some of the blowing is performed with CO2 generated by the reaction of water with the polyisocyanate, has become increasingly important. Such systems typically employ tertiary amine catalysts to accelerate both the blowing (reaction of water with isocyanate to generate CO2) and gelling (reaction of polyol with isocyanate) reactions required to make a foam. However, known tertiary amine catalyst compositions may give rise to objectionable releases of volatile and often malodorous materials into the air during foam manufacture and/or thereafter. The present invention addresses the issue of how to reduce such emissions, using certain catalyst compositions.